Seat belt buckle



Dec. 17, 1968 R. E. MEsHEw 3,416,201

SEAT BELT BUCKLE Filed Feb. 25. 1966 5? ENTOR.

ezel Wa/ze@ ATTORNEY United States Patent O 3,416,201 SEAT BELT BUCKLERobert E. Meshew, Birmingham, Mich., assignor to General MotorsCorporation, Detroit, Mich., a corporation of Delaware Filed Feb. 25,1966, Ser. No. 530,043 4 Claims. (Cl. 24-230) ABSTRACT THE DISCLOSURE Ina seat belt assembly, a lock plate is attached to one of the strap endsand is engageable with a buckle which is adjustably attached to theother strap end. The buckle comprises a frame which mounts a strapadjustment slide bar that is enclosed by a rear cover. The frameincludes channel-shaped sides and a locking boss struck out from thebase and engageable with the lock plate. A spring is secured to the baseand includes a pair of curved arms confined in the side channels forbiasing the inserted lock plate downwardly into engagement with thelocking boss. A front cover engages the spring and is confined withinthe side channels. The front cover includes a pair of depending curvedtabs which rockably engage the base and underlie the inserted lockingplate. Lifting causes pivoting or rocking of the cover member on thetabs which raise the lock plate against the bias of the spring arms andout of engagement with the locking boss to permit withdrawal.

This invention relates to buckle mechanisms, and more particularly itrelates to a lseat belt buckle which is adapted to cooperate with alatch plate to secure a body within the confines of the seat belt.

It should be clear that the subject buckle will have many different usessuch as the preferred embodiment wherein the buckle is attached to onelength of belt and engages a cooperating lock plate which is fastened toanother length of belt. This general type of buckle and lock plateassembly has common widespread use in automobiles for securingpassengers within a vehicle seat. With this widespread use of buckles inseat belt assemblies there is a need for a relatively simple andeconomical buckle which will effectively engage a lock plate.

It is, therefore, an object of this invention to provide a relativelysimple buckle which requires only its frame member to be of a strongmaterial as the remainder of the component parts are not subjected tothe loads on the seat belt assembly.

Other objects, features, and advantages of this invention will becomeobvious upon reference to the following detailed description and thedrawings depicting the preferred embodiment thereof, wherein:

FIGURE 1 is a plan view with parts broken away and in section;

FIGURE 2 is a sectional view taken in the plane of line 2-2 in FIGURE 1showing the buckle and lock plate in the engaged position;

FIGURE 3 is the same sectional view as FIGURE 2 showing the buckle andlock plate in the disengaged position;

FIGURE 4 is a cross sectional view taken in the plane of line 4-4 inFIGURE l; and

FIGURE 5 is a perspective exploded view of the component parts of thebuckle assembly.

FIGURE l shows a buckle attached to one segment of a belt 12 engaging alock plate 14 which also is attached to a belt 16. It should be notedthat the belts 12 and 16 may be separate lengths of belt as attached toxed anchors at their opposite ends such as in a seat belt assembly orthey may be the opposite ends of the same Mice length of belt. 'Illelock plate 14 may be any suitable plate-like structure having anaperture 18 therethrough forming a lock engaging shoulder 20, or otherequivalent lock-engaging structure.

The main structural element of the buckle 12 is a substantiallychannel-shaped frame 22 which has a base 24 and a pair of sides 26 withinturned flanges 28. The base 24 of the frame 22 has a large rectangularaperture 30 formed therethrough to receive the belt 12. The belt 12 isadjustably looped around a rectangular slide bar 32. The slide bar 32lits between U-shaped ribs 34 and 36 which are secured relative to eachother by means of a slide bar adjuster plate 38 and positioned withinthe frame 22 under the inturned flanges 28. This slide bar adjusterplate 38 is slidable within the frame 22 to thereby allow movement ofthe belt 12 around the slide bar 32 thereby allowing adjustment of thelength of the belt 12. The slide bar adjuster plate 38 further includesa U-shaped end rib 40 which closes one end of the frame 22.

The frame 22 has formed from its base 24 a locking boss or pawl 42having a substantially transverse locking edge 44. This boss 42 isadapted to extend through the aperture 18 in the lock plate 14 so thatthe transverse locking edge 44 abuts the retaining surface 20 in theaperture 18 thereby fastening the lock plate 14 to the buckle frame 22.It should be noted that the buckle frame 22 carries all of the loadtransmitted through the buckle assembly by way of the belts and thus isthe only portion of the buckle assembly 12 which requires a high degreeof structural integrity.

A cover 46 includes a decorative and relatively planar upper surface 48and offset rear portion 50# with slots 52 cut therethrough and a pair ofarms 54 bent inwardly from the sides of the portion 50. A pair of slits56 are cut into the cover 46 thereby providing openings for the inturnedflanges 28 on the frame 22 so that the cover 46 can be slid intoengagement with the frame 22 so that the upper decorative portion 48 ison top of the inturned flanges 28 and the rear portion 50 and theinturned arms 54 are positioned within the frame 22 underneath theinturned flanges 28. As best seen in the dashed lines in FIG- URE 1, theinturned arms 54 also extend away from the lower portion 50 so that inassembly with the frame 22 they underlie the latch plate 14 when it isin locking relation with the pawl 42. A spring member-60 is positionedwithin the frame so that its upturned feet 62 extend into the slots 52in the lower portion 50 of the cover 46 thereby fastening the spring 60to the cover 46. The spring 60 further has a slot 64 cut therethroughand a tab 66 which are adapted to cooperate with lanced portions 68 inthe base 24 of the frame 22 so that the tab 66 is positioned between thelanced portions 68 thereby fixing the spring 60 relative to the frame22. The spring member 60` also has a pair of spring arms 70 which extendforwardly underneath the inturned flanges 28 and overlie the lock plate14 when it is positioned over the boss 42. The spring arms 70 therebybias the lock plate 14 into locking engagement with the boss 42.

When release of the lock plate 14 from the buckle 12 is desired, thecover 46 is lifted slightly. as shown in FIG- URE 3, thereby causing thearms 54 to raise and disengage the lock plate 14 from the boss 42 whereit is free to be Withdrawn from the buckle. Thus, the cover 46 servesboth as a decorative cover and as a single piece release mechanism fordisengagng the lock plate from the buckle. Hence, the cover 46 can beconstructed from any suitable light weight metal as it does notwithstand any of the loads existing in the belt assembly. Thus, thisinvention provides a relatively simple and economical buckle which canbe used in combination with a standard lock plate to secure two beltmembers together. This buckle has very few parts and therefore will beeconomical and easy to assemble. This buckle also provides a lock platerelease mechanism which is incorporated with the decorative cover intoone single unit. Thus, a buckle assembly has been provided which solvesthe problems of high cost and complexity associated with the manyvarieties of buckle assembles now used in automobiles in conjunctionwith safety seat belts.

Although but one embodiment of this invention has been shown anddescribed in detail, it should be clear to those skilled in the art towhich the invention pertains that many changes and modifications may bemade thereto without departing from the scope of the invention.

I claim:

1. In combination with a pair of strap ends, a buckle attached to one ofthe strap ends and including a frame member having a locking boss formedintegrally with the base thereof, and a lock plate attached to the otherstrap end and insertable within the buckle into engagement with thelocking boss to interengage the buckle and lock plate, the improvementcomprising a spring member mounted on the frame member and having meansengaging the lock plate upon insertion of the lock plate within thebuckle to bias the lock plate into engagement with the locking boss, acover member attached to the spring member and pivotally mounted withinthe frame member in overlying relation to the spring member and lockingboss, and tab means formed integrally with the cover member andunderlying the inserted lock plate, the cover member causing the tabmeans to lift the lock plate against the spring bias and out ofengagement with the locking boss to enable withdrawal of the lock platefrom the buckle.

2. The combination of claim 1, wherein the frame member includes sidechannel portions and the spring member engaging means includes a pair ofcurved arms conned within the channel portions, the Icurved arms beingcompressible within the channel portions by the lock plate uponinsertion.

3. The combination of claim 2, wherein the cover member tab meansinclude a pair of depending curved tabs confined within the sidechannels and engaging the frame base to enable pivotal movement of thecover member, the tabs including portions underlying the inserted lockplate.

4. The combination of claim 3, wherein the buckle member includes a pairof lanced tabs and the spring member includes a portion confinedtherebetween to locate the spring member longitudinally of the framemember, the spring member including a pair of projections and the covermember including a pair of slots receiving the projections to locate thecover member longitudinally of the spring member and the frame member.

References Cited UNITED STATES PATENTS 3,256,576 6/ 1966 Klove.

FOREIGN PATENTS 396,487 l/ 1966 Switzerland.

1,385,512 12/1964 France.

BERNARD A. GELAK, Primary Examiner.

U.S. Cl. X.R. 24-196

